We are studying the properties of PG from human intervertebral disc by chemical and physical techniques (molecular sieve filtration, ultracentrifugation, viscosity and electron microscopy) in order to characterize their macromolecular structure and the size of the aggregates. PG are prepared from nucleus pulposus and annulus fibrosus obtained from autopsies of skeletally normal individuals. We intend to apply the information obtained from normal intervertebral disc to the study of specimens of intervertebral disc obtained at autopsy and surgery of individuals with "idiopathic" and paralytic scoliosis and with Scheuermann's disease. Electron microscopic studies of isolated PG from intervertebral disc will aid in the elucidation of their macromolecular organization. We are planning studies of intervertebral disc collagen in patients with the above mentioned diseases. We will continue our studies on PG of iliac crest biopsies from children with skeletal growth disorders such as achondroplasia, pseudoachondroplasia and several forms of spondyloepiphyseal displasia and try to correlate biochemical data with clinical, histological and electron microscopic abnormalities. BIBLIOGRAPHIC REFERENCES: In press - Pepsin Solubilized Collagen of Human Nucleus Pulposus and Annulus Fibrosus: W.R. Osebold and V. Pedrini, Biochim. Biophys. Acta. 1976.